Data Collection
Experts and case studies
The first step in exploring governance structures was to identify key experts working in different SESs around the planet. For this purpose, we defined experts as individuals with over 10 years of experience in a specific case study, encompassing both scientific expertise and practical knowledge26. Our panel of experts included scientists, practitioners, and local inhabitants, ensuring a diverse representation in each case study (Table S1 – supplementary material).
Socio-ecological systems and experts were selected purposively on the basis of the available literature on the SESs. It is crucial to note that in this study, each SES denotes a distinct relationship between a group of people and a specific resource. Consequently, if experts identified multiple relationships within the same human group (e.g., variations in governance structures between seasons), each was considered a separate SES. Therefore, certain human groups were categorized as having multiple SESs. In total we evaluated six human groups and 11 SESs.
SES descriptions were obtained mainly through secondary information. We also asked experts about interactions with external stakeholders, external influences on governance structures, and technological levels. Following the Chiaravalloti et al.6 classification of governance structures, together with experts, we categorized case studies as having management rules (indicative of clear boundaries or limitations) or social rules (marked by flexible boundaries and rules aimed at maximizing resource extraction).
Experts' evaluation of predictability to resource access
After elucidating the governance of each case study, experts were tasked with quantifying the level of predictability of access to natural resources for each specific SES (e.g. level of predictability of Traditional Amazonians accessing Brazil nuts in the forest, or level of predictability of Pantaneiro fishers accessing fish in the Pantanal).
The level of predictability in accessing resources was measured through a three-step interactive process. First experts were asked to define a measure of a good day for the specific SES. We defined “good day” as a day or hunting/gathering/fishing excursion for which a household of that specific SES would feel satisfied with the quantity of resources they had accessed. For instance, a certain quantity of animals hunted by the Agat in Philippines, or Massai cattle being able to access water and forage during the dry season. The “good day” measure was determined by consensus among all experts in each SES.
Following the consensus on what would be a good day in each SES, we asked experts to estimate the level of predictability of local people achieving the “good day” target. We used a structured expert elicitation protocol proposed by Hemming et al.26 (the Investigate, Discuss, Estimate, and Aggregate (IDEA) protocol) to establish this accurately. The IDEA protocol comprises two phases. Initially, experts provided an average score, a confidence interval, and the likelihood that the confidence interval accurately represents the real value (ranging from 50% to 100%). The question we asked was about the number of good days/trips out of 10 that a household in that specific SES would have (not necessarily 10 consecutive days, but rather 10 consecutive attempts to access and use resources). We also asked experts to answer the same questions should strict boundaries be implemented in that SES (questionnaires in supplementary material)
Following individual consultations with experts from each SES we normalized all answers to 80% confidence interval as proposed by Hemming et al.26. Then, we showed all answers to the experts of the same SES to potentially adjust their responses based on aggregated findings. This iterative process enabled experts to compare and refine their assessments. The final score was the average number of good days, and average confidence interval of all experts’ answers.
The number of experts interviewed for each case study ranged from three to six, totalling 48 entries from 35 experts. Each expert was interviewed at least three times. Interviews were carried out between June 2022 and December 2023. Interviews were conducted in Portuguese, English, and Spanish. Ethical approval was obtained from the Ethics Committee at Imperial College London (approval number 21IC7307).
Unit of Evaluation
Our study did not focus on specific communities but rather on SESs of users exhibiting similar historical resource utilization, technological levels, identity, and ecological dynamics. Consequently, experts interviewed for a particular SES often referred to different communities inhabiting the same area. Any disparities in resource utilization practices between communities are detailed in the respective case study descriptions (see supplementary material).
Case Studies
In total, we examined 11 SESs, each illustrating a distinct governance structure employed by human groups to utilize and access natural resources. These SESs represented diverse groups residing in various regions worldwide. Further elaboration on these groups and their respective case studies is provided in the supplementary material.
Maasai Pastoralists, Rangelands, Kenya / Tanzania: Pastoralism, has been a way of life in North, East, West and South Africa for at least 4,000 years7. In Maasai society, cattle hold central significance fulfilling basic needs of food, clothing, and shelter. They also function as wealth store, social and economic currency, with ownership of large herds denoting wealth and status. Maasai pastoralist herds share the African savanna grasslands with a wide range of iconic wildlife species15.
Maasai pastoralists were divided into two case studies. 1) Pastoralists Africa rangelands wet season (PW): During the wet season, herds disperse across the grazing lands in response to the abundant and widely distributed grazing and surface water. Transhumance takes the herds away from permanent water of rivers, swamps or highland drought refuges, to make the most of higher quality rainfed forage. During this wet season period of abundance, elders customarily confer to delineate and set aside specific grazing areas for later dry season use. The elders communicate these restrictions and determine penalties to be imposed on any herders entering these reserved areas, while warrior age sets monitor and enforce observance of the grazing rules7; 2) Pastoralists Africa rangelands dry season (PD): When dry seasons lengthen into drought and resource scarcity becomes extreme, pastoralists scout for and elders confer over areas with better forage and water access. Pastoralist strategies are adjusted day to day through constant information sharing within social networks on key resources. Homesteads pool their livestock and pastoral labour to ensure difficult and dangerous movements can be carried out safely. During droughts, pastoralists seek to maintain access to rangeland resources beyond their homesteads and any immediate commons, leveraging social networks to find grazing. They make often difficult and dangerous long-distance treks including cross-border movements and passage through increasingly constrained corridors between croplands they must not damage, and wildlife reserves they may not enter6,15.
Traditional Amazonians, Rainforest, Brazil: Traditional people of the Amazon Rainforest are predominantly descendants of migrants who settled in the Amazon in the late 19th and early 20th centuries to work as rubber tappers47. Following the collapse of the rubber market in Brazil, they diversified their livelihoods by accessing areas once owned by rubber landlords to extract other resources such as fish, mammals, and nuts. In the 1990s, the Brazilian government began creating sustainable use protected areas to safeguard their livelihoods48. These areas, though belonging to the government, grant local people living permits under the condition that they implement their own sustainable resource governance system. Most of the SES are not generalized for all the Amazon region. They refer to the areas in which the experts carried out their work (supplementary material).
We looked at four types of governance structures in these areas: 3) Hunting Large Game (HLA): hunters ambush prey within large forest patches facilitated by the sharing of information, which is then followed by resource sharing within the community. 4) Hunting Small Game in household croplands (HAS): hunting of small mammals in household croplands takes place when small prey such as black agouti or collared peccaries enter private small croplands known as “roçados”, and no one is allowed to hunt the prey but the owner of the “roçado” 49; 5) Brazil nut harvesting (BA): In the reserves analysed (regions within the Acre state in Brazil), Brazil nut harvesting areas (locally known as castanhais) is characterised by a regime in which each household has their own forest patch (~400 ha) and seasonally harvest nuts from within the area28. 6) Arapaima fishing (AA): community members established a system with clear management rules based on fishing quotas of arapaima, clear extraction limits with associated sanctions and collaborative seasonal fish counts16.
Pantaneiros fishers, Wetland, Brazil: The Pantaneiro fisher communities primarily inhabit the main rivers of the Pantanal wetland, utilizing river branches and floodplain areas for fishing sites. These communities, existing in the region for thousands of years, have integrated with foreigners over the past 200 years, including former slaves and individuals from Paraguay50.7) Fishing (PT): fishers in the Pantanal must adapt to the seasonal flood pulses which constantly change access to water bodies. To navigate this, local families share information in daily tea-drinking sessions about good fishing grounds with other community members, advising of changes in water levels and therefore access to fishing areas23.
Garifuna fishers, Honduras: The Garifuna community descend from West African escaped and marooned slaves, who comingled with native Arawak on the Caribbean Island of St. Vincent51. They were originally taken to St Vincent, before making their way to Roatan, Honduras, where they settled and communities formed along the north shore of Honduras, and now extend from Belize through Nicaragua. A rigid gender division of labour is observed within Garifuna communities, with women responsible for childcare and other household chores, and tending subsistence agriculture plots, while men are primarily engaged in fishing activities51. 8) Fishing coral reef (CH): Coral reef associated fisheries are the primary target species of Garifuna fishermen, which underpin the food security and livelihoods of these communities52. Reef fisheries are accessed by small wooden vessels with low horsepower engines or paddle53. Fishermen move freely throughout fishing areas within their range, and information is shared freely between Garifuna fishermen, such as which fishing grounds are productive, upon return from fishing excursions. However, this information is not shared with other ethnic groups who share fishing grounds in areas along the Honduran northshore53.
Agta hunter-gatherers, Rainforest, Philippines: The Agta, an indigenous Filipino community, inhabit the tropical forests along the northeastern coast of Luzon in the northern Philippines. Their economy is primarily based on hunting, fishing, and gathering, supplemented by some small-scale agriculture and wage labour54. The Agta live in small, mobile groups. 9) Hunting: hunters move freely throughout the forest trying to find game. Meat is typically shared widely with members of their own residential group55.
Warufiji fishers, Rufiji Riverscape, Tanzania: At least eight ethnic groups inhabit the floodplain, referred to collectively as the Warufiji by local residents. Local livelihood strategies are dominated by farming (primarily maize and rice) and fishing. Fishing occurs year-round but with strong seasonal changes in effort and gear dictated by the flood-cycle56. The Rufiji River is the longest river in Tanzania, draining some 20% of the country’s land area through its major tributaries38. The river has an annual flooding pattern, beginning around December and generally reaching peak water levels in April, but the timing, duration and level of flooding is highly variable and difficult to predict, though completion of a hydropower dam in 2023 has changed these dynamics for downstream communities. When water levels do exceed a certain threshold, riverine water flows into the permanent lakes through temporary channels. 10) Flooplain fishing (RR): Fishing on the floodplain at high water is largely limited to subsistence catches from gill nets set out on residents’ flooded fields. The most productive floodplain fishing happens as waters are rising or falling, when fish migrate through temporary channels 57. 11) Fishing in the Lakes and channels (RL): Prior to their forced displacement from the floodplain to the bordering terraces in the 1960s, communities set clear limits on who and how people accessed floodplain waterbodies once the high waters had receded. People had to respect clans’ ownership of lakes and share fishing opportunities and fish with other clans56. Today, no controls exist on temporary floodplain ponds. Although communities have bylaws to manage their permanent lakes on the high terrace, they struggle to enforce these. Rights to set traps on the most predictable temporary channels on the rising and falling flood are still in place and negotiated among fishers and field owners31.
Methods References
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